1. Field of the Invention:
This invention relates to a closed circuit television apparatus for a supervisory system, and more particularly to a closed circuit television apparatus in which a television camera is remotely controllable.
2. Description of the Prior Art:
A closed circuit television apparatus of the type mentioned above is known in which one television camera is remote-controllable from a plurality of supervisory stations. In this apparatus, the remote-controllable television camera is located at a place to be observed. At each of the supervisory stations, a controlling device for remote controlling the operations of the television camera, such as make-and-break of a power, make-and-break of a wiper, and rotating the coordinates of the television camera, such as up-down (tilting), left-right (panning), far-near (focusing) and tele-wide (zooming) is located. Between the television camera and the controlling devices, a distributor is used for distributing a video signal from the television camera to the controlling devices. Each controlling device includes a control panel for generating a plurality of control signals to control the television camera, and a monitor for receiving the video signal from the television camera and for displaying a picture or image corresponding to the video signal.
A problem with this conventional closed circuit television apparatus is that since separate transmission lines are employed for transmitting the video signal generated by the camera and the control signals generated by the controlling devices, many cables must be built between the controlling devices and the television camera which is complex and expensive.